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MM: Fix bug when mapping a region with a VMO with non-zero offset.

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This commit is contained in:
Andreas Kling 2018-12-29 03:34:24 +01:00
parent 46ce47a984
commit 0dd5279eb1
1 changed files with 5 additions and 4 deletions
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9
Kernel/MemoryManager.cpp
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@ -426,7 +426,7 @@ void MemoryManager::unquickmap_page()
auto page_laddr = LinearAddress(4 * MB);
auto pte = ensure_pte(m_kernel_page_directory, page_laddr);
#ifdef MM_DEBUG
auto old_physical_address = pte.physicalPageBase();
auto old_physical_address = pte.physical_page_base();
#endif
pte.set_physical_page_base(0);
pte.set_present(false);
@ -472,14 +472,15 @@ void MemoryManager::map_region_at_address(PageDirectory* page_directory, Region&
#ifdef MM_DEBUG
dbgprintf("MM: map_region_at_address will map VMO pages %u - %u (VMO page count: %u)\n", region.first_page_index(), region.last_page_index(), vmo.page_count());
#endif
for (size_t i = region.first_page_index(); i <= region.last_page_index(); ++i) {
for (size_t i = 0; i < region.page_count(); ++i) {
auto page_laddr = laddr.offset(i * PAGE_SIZE);
auto pte = ensure_pte(page_directory, page_laddr);
auto& physical_page = vmo.physical_pages()[i];
auto& physical_page = vmo.physical_pages()[region.first_page_index() + i];
if (physical_page) {
pte.set_physical_page_base(physical_page->paddr().get());
pte.set_present(true); // FIXME: Maybe we should use the is_readable flag here?
if (region.cow_map.get(i))
// FIXME: It seems wrong that the *region* cow map is essentially using *VMO* relative indices.
if (region.cow_map.get(region.first_page_index() + i))
pte.set_writable(false);
else
pte.set_writable(region.is_writable);